the 1/4" in. scale eliminator is a highly-reliable, durable product from dial. this cartridge attaches to 1/4" copper or poly tube water line using 1/4" cc brass fittings. it controls scale build-up and corrosion in coolers, while its special formula holds minerals in suspension by raising the solubility level of the water. this cartridge is for outdoor use and is designed to last up to 3 months.